SURFACE MICROSTRUCTURE OF ZR41.25TI13.75CU12.5NI10.OBE22.5, A BULK METALLIC-GLASS

The surface of Zr41.25Ti13.75Cu12.5Ni10.0Be22.5, a bulk metallic glass prepared by RF induction melting, has been imaged using atomic force microscopy. The untreated surfaces were very smooth; features were no higher than 3 nm over a 10 x 10 mu m region, comparable to many polish ed surfaces, Two types of microstructure were also observed; periodic striations forming either a striped or a checkered structure were pres ent, with wavelengths between 1 and 2 mu m, and amplitude of approxima tely 2 nm; in other cases, ''cracked mud''-like patterns were observed . These microstructures could be related to strain-induced surface rou ghening; preliminary calculations an presented that are consistent wit h this hypothesis.